Texas Winter 2012-2013

[Ntxw]

Personally id go with full latitude trough though and yes there isnt much cold air pooling in the models it seems, but if it came from Siberia.....

That's where the SSW comes in. If the event propagates as expected the cold air will sink from above the troposphere via the collapsed vortex. Not from regular landmasses, if what I read is correct

[TeamPlayersBlue]

Personally id go with full latitude trough though and yes there isnt much cold air pooling in the models it seems, but if it came from Siberia.....

That's where the SSW comes in. If the event propagates as expected the cold air will sink from above the troposphere via the collapsed vortex. Not from regular landmasses, if what I read is correct

Agreed. The HP's dont look very dense, but it could be just right for us. We dont want suppression or air that is too dry.

[orangeblood]

Below is the day 10 forecast from the 12Z GFS ensembles...



About as textbook as you can get for an Arctic Outbreak across the lower 48 and with the block forming over Greenland this bitterly cold air should get locked over North America for quite some time. Notice the V shaped block forming over the top of North America - this will force the Polar Vortex to set up shop over Southern Canada and send Arctic High after Arctic High down into the lower 48. Incredible pattern setting up if you like cold weather!!!

[Longhornmaniac8]

Looking at the radar returns, it looks like there's quite a bit of moisture in the upper levels, but very little is reaching the ground, at least here in NW Austin. I realize this is what the pro mets have identified as the reason for a lack of precipitation in the area. Are others on here under the assumption that the air column closer to the surface will saturate more as the day goes on?

Also, what about temperature? I'm not seeing anything that's projecting Austin to get close to freezing at the surface any time in the next 24 hours. So is it unrealistic to expect any accumulation?

We're now well into the "watchcast" period, so what are people seeing in terms of what's actually going on? Is the moisture in the region about what was expected by the models over the last couple of days?

I suppose it's a good thing that the Austin NWS has steadily moved the probability of freezing precip to the east, and has hoisted WWAs for the western part of their region.

Let it snow!

Cheers,
Cameron

[wxman57]

Are today's model runs still showing potential for severe cold in the long range?

Potential for cold? Yes. Severe cold? That depends. What's severe? 12Z GFS, for example, forecasts a low of 23F in Dallas on the 17th of the month. That's the coldest over the next two weeks, at least according to the latest GFS run. The GFS is showing some cross-Polar flow and movement of cold air southward out of northern Canada by mid month, but there's a question of just how cold the airmass that comes down will be.

[Ntxw]

Potential for cold? Yes. Severe cold? That depends. What's severe? 12Z GFS, for example, forecasts a low of 23F in Dallas on the 17th of the month. That's the coldest over the next two weeks, at least according to the latest GFS run. The GFS is showing some cross-Polar flow and movement of cold air southward out of northern Canada by mid month, but there's a question of just how cold the airmass that comes down will be.

The AO finally went a little positive today for you sir. You should get a couple days to relax next week though not exactly hot. Have you had any bike rides lately or plan to?

[dhweather]

Are today's model runs still showing potential for severe cold in the long range?

Potential for cold? Yes. Severe cold? That depends. What's severe? 12Z GFS, for example, forecasts a low of 23F in Dallas on the 17th of the month. That's the coldest over the next two weeks, at least according to the latest GFS run. The GFS is showing some cross-Polar flow and movement of cold air southward out of northern Canada by mid month, but there's a question of just how cold the airmass that comes down will be.

I'm leaning towards cold fronts that bring some sub freezing nights and relatively cold days to the DFW area, but I just don't think it's going to be anything compared to 89 or other years.

My rule #1 in weather is to never trust model forecasts beyond seven days. So we will have to wait until next week to get an idea of where we are headed.

[CaptinCrunch]

Are today's model runs still showing potential for severe cold in the long range?

Potential for cold? Yes. Severe cold? That depends. What's severe? 12Z GFS, for example, forecasts a low of 23F in Dallas on the 17th of the month. That's the coldest over the next two weeks, at least according to the latest GFS run. The GFS is showing some cross-Polar flow and movement of cold air southward out of northern Canada by mid month, but there's a question of just how cold the airmass that comes down will be.

It's not how cold it will get, but rather how long the cold last. 23 is fine for a night or 2, but 30 and below for 3-5 days can be an issue.

[cycloneye]

I know that the majority of the Texas members will want to see their yard like this photo shows at El Paso.

[Ntxw]

Latest 12z Euro run

[wxman57]

Potential for cold? Yes. Severe cold? That depends. What's severe? 12Z GFS, for example, forecasts a low of 23F in Dallas on the 17th of the month. That's the coldest over the next two weeks, at least according to the latest GFS run. The GFS is showing some cross-Polar flow and movement of cold air southward out of northern Canada by mid month, but there's a question of just how cold the airmass that comes down will be.

The AO finally went a little positive today for you sir. You should get a couple days to relax next week though not exactly hot. Have you had any bike rides lately or plan to?

No biking since before Christmas. Was riding 100 miles/week before then. We plan to ride this Sat/Sun but I may not have any skin showing. Hate riding like that. Maybe we can get all that nasty cold drained out of Canada and move on to spring temps by February...

One good thing (for me), is that even though the snow pack is fairly far south, it's relatively shallow in most areas. That means it can quickly melt and the snow line retreat northward unless it's replenished in the next few weeks.

[iorange55]

Wow. That is quite the run...it's not often you see runs like that.

[Comanche]

since i cannot decipher exactly what those euro maps mean, anyone care to elaborate? I need met for dummies book!

[Ntxw]

Wow. That is quite the run...it's not often you see runs like that.

If you loop the run, you can see the mass of air being drained out of Russia across the pole, very fascinating. I've heard of "cross polar flow" a lot but I think that's the first time I've seen it move on a map.

[orangeblood]

Wow. That is quite the run...it's not often you see runs like that.

If you loop the run, you can see the mass of air being drained out of Russia across the pole, very fascinating. I've heard of "cross polar flow" a lot but I think that's the first time I've seen it move on a map.

Yes, very fascinating!! The Euro has been playing playing catch up with the GFS lately. The coldest air in the entire globe should begin to funnel down into North America and get locked in, right in the heart of winter...unfortunately, the gas and electric bills will sky rocket this month

[TeamPlayersBlue]

Wow. That is quite the run...it's not often you see runs like that.

If you loop the run, you can see the mass of air being drained out of Russia across the pole, very fascinating. I've heard of "cross polar flow" a lot but I think that's the first time I've seen it move on a map.

Yes, very fascinating!! The Euro has been playing playing catch up with the GFS lately. The coldest air in the entire globe should begin to funnel down into North America and get locked in, right in the heart of winter...

Saw it for the first time i think last year on a map that didnt pan out and it was beautiful. The HP just glided into the map all the way to southern Canada.

[lukem]

It’s starting to snow pretty hard in Midland for the first time today. Big flakes.

[downsouthman1]

Looking at the radar returns, it looks like there's quite a bit of moisture in the upper levels, but very little is reaching the ground, at least here in NW Austin. I realize this is what the pro mets have identified as the reason for a lack of precipitation in the area. Are others on here under the assumption that the air column closer to the surface will saturate more as the day goes on?

Also, what about temperature? I'm not seeing anything that's projecting Austin to get close to freezing at the surface any time in the next 24 hours. So is it unrealistic to expect any accumulation?

We're now well into the "watchcast" period, so what are people seeing in terms of what's actually going on? Is the moisture in the region about what was expected by the models over the last couple of days?

I suppose it's a good thing that the Austin NWS has steadily moved the probability of freezing precip to the east, and has hoisted WWAs for the western part of their region.

Let it snow!

Cheers,
Cameron

The column will saturate from the top-down, as well as reduce temps during the process of precip falling, even if it's virga. http://www.wrh.noaa.gov/zoa/mwmap2.php?map=zfw. Just look @ ECU (Rocksprings, Edwards County Airport). I've watched the temp there drop like 3 degrees from earlier as snow was falling there earlier today. Now, our temps are too high. But I believe that'll change. (Not official).

[Ntxw]

It’s starting to snow pretty hard in Midland for the first time today. Big flakes.

Get us pictures if you can, we love those! Another heavy band will be moving into Midland and especially Odessa soon

[vbhoutex]

Are today's model runs still showing potential for severe cold in the long range?

Potential for cold? Yes. Severe cold? That depends. What's severe? 12Z GFS, for example, forecasts a low of 23F in Dallas on the 17th of the month. That's the coldest over the next two weeks, at least according to the latest GFS run. The GFS is showing some cross-Polar flow and movement of cold air southward out of northern Canada by mid month, but there's a question of just how cold the airmass that comes down will be.

I'm leaning towards cold fronts that bring some sub freezing nights and relatively cold days to the DFW area, but I just don't think it's going to be anything compared to 89 or other years.

My rule #1 in weather is to never trust model forecasts beyond seven days. So we will have to wait until next week to get an idea of where we are headed.

I am in general agreement with you on this. However, I am starting to see enough in the long ranges, not in just one model, that makes me lean more towards the longer, colder outbreak camp after the middle of January and possibly into February. Is some of it wishful thinking? Of course it is. But there are a lot of signals showing that are at a minimum pointing towards what I would call a true polar cold outbreak. I've been through all the analog years mentioned here in Houston and I can tell you it wasn't fun at all, but I am a weather nerd, and I am trying to look ahead in case I need to do some more preparation.
Heavier clouds have now moved into the Houston area so we only got a few hours of peeks at sunshine today which toasted us to a 51f high. I expect the temps to start falling again and the moisture is obviously moving in also. Question is will it moisten up enough to give us any precip of any kind.